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Development of Web-based remote monitoring system for the moving-actuator artificial heart

ASAIO Journal 2000年第2期46卷 199-199页

作者： Chung, Jinhan Lee, Jihoon Jo, Yungho Min, ByoungGoo Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University Department of Biomedical Engineering Seoul National University College of Medicine

The remote monitoring system including hemodynamic information and pump status of the implanted animal could be helpful during the in vivo experiment or clinical trial for an artificial heart implantation. In order to monitor the course of the in vivo experiment continuously and anywhere, web-based remote monitoring system was developed, which could be monitored pressures (AoP, LAP, RAP, PAP) and flow information as well as the pump operating conditions. The system consists of the several parts including data sending, storing, viewer part. The data sending part was constructed using component object model and the viewer part was constructed using the Java applet. In addition, the dialog box was introduced to communicate each other instantly and the alarming function was also introduced when the hemodynamic values were out of the desired ranges. The developed remote monitoring system was applied during the in vivo experiment of the VVAD implantation for 1 month and showed designed work without fail.

关键词： Heart valve prostheses

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Determination of metachronal wave direction and wavelength of beating ciliary cells from correlation map using digitized images

Determination of metachronal wave direction and wavelength o...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Won Jin Yi Kwang Suk Park Chae Seo Rhee Chul Hee Lee Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University Seoul South Korea Department Of Biomedical Engineering College of Medicine Seoul National University South Korea Department of Otolaryngology College of Medicine Seoul National University South Korea

ISBN: (纸本)0780364651

By calculating correlation factor between two signals from different sites using digitized images of beating ciliary cells, the direction of uniphase lines was defined and the metachronal wavelength was calculated along the direction perpendicular to this. From the correlation map showing spatially the phase difference between beating cilia, the direction of uniphase lines was determined by the principal axis method. The metachronal wavelength of 8 objects for TSA was in the range of 50-70 pixels, Under our measurement system, the mean wavelength of metachronal wave was found to be 6.24/spl plusmn/0.27[/spl mu/m].

关键词： biomedical imaging Wavelength measurement Electrostatic discharge Video recording Image converters biomedical engineering Propulsion Phase measurement Neoplasms Neurosurgery

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PIV MEASUREMENTS OF FLOW DISTAL TO POLYURETHANE HEART VALVE PROSTHESIS UNDER STEADY AND PULSATILE FLOW CONDITIONS

PIV MEASUREMENTS OF FLOW DISTAL TO POLYURETHANE HEART VALVE ...

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ASME 1999 International Mechanical engineering Congress and Exposition, IMECE 1999

作者： Kim, Jung Kyung Sung, Jaeyong Yoo, Jung Yul Chang, Jun Keun Min, Byoung Goo Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University Seoul Korea Republic of Department of Mechanical Engineering Seoul National University Seoul Korea Republic of School of Mechanical and Aerospace Engineering Seoul National University Seoul Korea Republic of Institute of Advanced Machinery and Design Seoul National University Seoul Korea Republic of Department of Biomedical Engineering College of Medicine Seoul National University Seoul Korea Republic of

ISBN: (纸本)9780791816400

Hemodynamic performance of a polyurethane heart valve prosthesis was evaluated in comparison with that of Bjork-Shiley Monostrut mechanical valve in steady and pulsatile flow. Pressure losses through the valves were obtained from the streamwise pressure distributions downstream of the valves under steady flow condition. Unsteady and turbulent flow through the heart valve prostheses were investigated using PIV in conjunction with the opening behaviors of valve leaflets. Direct measurements of the wall shear stress by hot-film anemometry (HFA) were compared with the PIV data. By examining the velocity field downstream of the polyurethane heart valve, it is known that high shear stress regions exist at the interface between strong axial jet flows along the wall and vortical flows in the central area. In addition, there are large recirculation regions near the valve. where thrombus formation can be induced by accumulation of damaged blood cells. A correlation between the flow pattern downstream of the valve and the corresponding opening posture of the polyurethane valve leaflet gives useful data necessary for improved design of the superstructure and leaflet geometry of the valve. © 1999 American Society of Mechanical Engineers (ASME). All rights reserved.

关键词： Valves (mechanical)

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Morphological classification of sperm heads using artificial neural networks

Morphological classification of sperm heads using artificial...

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9th World Congress on Medical Informatics, MedInfo 1998

作者： Yi, Won Jin Park, Kwang Suk Paick, Jae Seung Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University Korea Republic of Department of Biomedical Engineering Seoul National University Korea Republic of Departmemt of Urology Seoul National University Korea Republic of

ISBN: (纸本)9051994079

In male reproducible health and fertility and IVF (in-vitro fertilization), morphological analysis of sperm has been most important. But the traditional tools for semen analysis are subjective, imprecise, inaccurate, difficult to standardize, and reproduce mainly due to their manually oriented operations. The purpose of morphological analysis of sperm is to microscopically type-classify sperm according to their morphological characteristics of heads. Until now, the strict criteria method has long been used in clinic to discriminate normal sperm from abnormal. This method cannot classify the diverse groups of abnormal sperm in detail and shows large variations in inter-operators and intra-operator. In this paper, we have studied a new method of sperm morphological classification using artificial neural networks that are widely used in pattern recognition and image processing. With a multi-layer perceptron trained by the error back-propagation algorithm, profile features from digitized sperm images were classified into four classes that consisted of one normal group and three abnormal groups according to their morphological characteristics. © 1998 IMIA. All rights reserved.

关键词： Multilayer neural networks

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Measurements of absorption coefficients within biological tissue in vitro

Measurements of absorption coefficients within biological ti...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Nam Jung Kim Hyun Soo Lim Interdisciplinary Program of Biomedical Engineering Major Chungnam National University South Korea Department of Biomedical Engineering College of Medicine Chungnam National University South Korea

The authors have examined the absorption coefficients of biological tissue in vitro. To develop the medical instruments for most applications, they have used as a light source the specific fixed wavelengths of lasers. So there are some restrictions while using the optical properties of biological tissue. To broaden the selection of wavelength, the authors experimented with 660/spl sim/940 nm on the highly scattering turbid medium to find out optical properties. The results shows that the absorption coefficients are different depending on wavelength and for each biological tissue.

关键词： Biological tissues In vitro Optical scattering biomedical optical imaging Optical sensors Light scattering Light sources X-ray scattering Electromagnetic wave absorption Equations

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Automatic control of assist flow in totally implantable left ventricular assist device using variable pump rate

Automatic control of assist flow in totally implantable left...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Jonghoon Choi Jaesoon Choi Youngho Jo Wukeun Kim Byunggoo Min Interdisciplinary Program of Medical and Biological Engineering Graduate School Japan Department of Biomedical Engineering College of Medicine Seoul National University South Korea

In this study, the automatic control algorithm in implantable left ventricular assist device to regulate cardiac output to the extent of preventing atrial-collapse and the high left atrial pressure (LAP) is proposed. Intersac pressure (ISP) waveform which reflects the status of left atrial pressure is used in automatic control. By analyzing the relationship between LAP and the negative peak of ISP, the equation for making the reference of PI-controller was set. By using the reference equation the proposed automatic controller which regulates the assist flow was designed. Through mock circulatory experiments and animal experiment, the automatic control algorithm was evaluated.

关键词： Automatic control Equations Blood Algorithm design and analysis biomedical engineering Pi control engineering in medicine and biology Educational institutions Electronic mail Animals

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Development of remote diagnosis system integrating digital telemetry for medicine

Development of remote diagnosis system integrating digital t...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Young Han Nam Zeehun Halm Young Joon Chee Kwang Suk Park Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University Seoul South Korea Department of Biomedical Engineering College of Medicine Seoul National University Seoul South Korea

We developed the system which enables a patient to be treated at home during their daily life through digital telemetry and public communication line. In this study, remote diagnosis system based on video conferencing and wireless telemetry system were integrated together to form a remote monitoring homecare system, and the overall system underwent the validation. Test ECG signals were transmitted wirelessly not hindering a patient's movement in one floor of our building, and the stability was assessed. The signals were transmitted to remote host via ISDN, with a patients voice and moving image. To control the system and manage files remotely, the interactive model was devised for this study.

关键词： Telemetry Medical treatment Videoconference Remote monitoring Testing Electrocardiography Floors Stability ISDN Control system synthesis

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Development of videostrobokymography for the quantitative analysis of laryngeal vibratory pattern

Development of videostrobokymography for the quantitative an...

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9th World Congress on Medical Informatics, MedInfo 1998

作者： Lee, Jae Sung Kim, Eomjun Park, Kwang Suk Sung, Mi Young Sung, Myung-Whun Kim, Kwang Hyun Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University Seoul Korea Republic of Department of Computer Science Inchon University Inchon Korea Republic of Department of Biomedical Engineering College of Medicine Seoul National University 28 Yungun-Dong Chongno-Gu Seoul 110-744 Korea Republic of Department of Otolaryngology Head and Neck Surgery Seoul National University Seoul Korea Republic of

ISBN: (纸本)9051994079

We developed a new analysis technique for the assessment of irregular vibratory movement of vocal folds. Successive frames of pre-recorded video images from videostroboscopy were transferred to computer memory and vibratory track of one selected point was described as a waveform by displaying the same lines of all frames along the vertical direction. Glottal area waveform, which was normalized with glottal length, was composed to quantitatively assess the overall vibratory pattern of vocal folds. By applying this technique, irregular vibratory patterns of multiple regions, such as asynchronized registration of glottal cycles, could be easily visualized It would be possible to monitor and analyze the pathologic changes of vocal fold movement by means of this newly developed system. © 1998 IMIA. All rights reserved.

关键词： Speech

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A study on the integration and synchronization of video image using H.261 in polysomnography

A study on the integration and synchronization of video imag...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Mee-Hye Choi Hae-Jeong Park Joo-Man Han Do-Un Jeong Kwang-Suk Park Inst. of Biomedical Engineering Department of Biomedical EngineeringCollege of Medicine Seoul National University South Korea Interdisciplinary Program of Medical and Biological Engineering Major Seoul National University South Korea Department of Psychiatry College of Medicine Seoul National University South Korea Department of Biomedical Engineering College of Medicine Seoul National University Seoul South Korea

The importance of the video monitoring during polysomnographic recording is increasing, but the analog-taped storage method currently in use has difficulties in random access and synchronization with the polysomnographic data. To overcome these limits we need to develop the digitalized integration and synchronization method. The digitization of the moving image during sleep requires at least the quality of detecting the relatively fast movement. It also requires the minimal volume of data for the storage and communication. We analyzed the two standards of digital moving image compression to find the optimal storing format for the video image during sleep. Based on this analysis, we developed the integration method using the format H.261, which has better performance than MPEG-1 in low bit rate of 128 kbps. We also used the QCIF format in H.261 to increase the frame rate, and added the time index to H.261 format to support random access. We synchronized these video images with the polysomnographic data.

关键词： Sleep Video compression biomedical engineering biomedical imaging Educational institutions Image coding Patient monitoring Image storage Cameras engineering in medicine and biology

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Nonlinearity changes of 24 hour heart rate variability in children with tetralogy of Fallot

Nonlinearity changes of 24 hour heart rate variability in ch...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Jong-Min Lee Chung-Il Noh Kwang-Suk Park Interdisciplinary Program in Medical and Biological Engineering Major Seoul National University South Korea Department of Pediatrics Seoul National University Seoul South Korea Department of Biomedical Engineering Seoul National University Seoul South Korea

It has been reported that sudden cardiac death and ventricular tachycardia can occur after treatment of tetralogy of Fallot (TOF). It is likely that TOF has effect on the heart rate variability because of the ventricular arrhythmia. We evaluated how complex and periodic dynamics of heart rate occurred in the normal children (group A, n=13) and TOF children (group B, n=13) throughout 24 hours. We examined each ECG data on 24-hour Holter ECG segmented into 1-hour length. We analyzed each HR time series, and quantified the overall complexity of each HR time series by its correlation dimension. We also calculated the power spectrum of HR, and obtained low-frequency component (0.08-0.15 Hz) and high-frequency component (0.15-0.4 Hz). We compared the results between group A and B. Group B had lower correlation dimension (4.055/spl plusmn/0.4134 vs. 4.9310/spl plusmn/0.2054, p<0.05) than group A, even though there were no significant differences in the low-(0.9864/spl plusmn/0.5598 vs. 1.5560/spl plusmn/0.8325, p<0,05) and high-(1.1168/spl plusmn/0.1.1448 vs. 0.9271/spl plusmn/0.6528, p<0.05) frequency components. It can be concluded that HR time series of group B are more regular than those of group A, and that correlation dimension reveals a nonlinear characteristics of HR time series which is not determined in the frequency domain.

关键词： Heart rate variability Pediatrics Electrocardiography Frequency domain analysis Heart rate Automatic control Time domain analysis Hafnium biomedical engineering Control systems

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